The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.
Refrigeration or freezing of food products is ubiquitous today. Freezing is the current standard method for food preservation, from commercial walk-in/drive-in equipment, to mobile refrigerator/freezer units, to small freezers located in households. Most of the food purchased frozen comes from commercial freezers; fresh food is introduced into household refrigerator/freezers with small freezers to preserve food for consumption as needed. Commercial walk-in/drive-in freezers freeze food products on a large scale, preparing the food for shipment around the corner or around the world. Yet current freezing methods were invented long ago and few improvements have been introduced to the food preservation industry. As a result, current refrigeration and freezing technology and techniques are inefficient and harmful to the environment.
Refrigeration, freezing, or air conditioning may generally describe a method to transfer heat from one area to another. Various appliances and methods exist to create the desired heat transfer. However current methods are inefficient and expensive to operate. Conventional methods of refrigeration use a freezing process where coolant absorbs the heat from the refrigerator or freezer through the evaporator coils and releases heat into the surrounding area through condenser coils. Conventional freezers release this heat into the surrounding room. Current freezing methods are also expensive and inefficient due to current defrost technologies. The evaporator coils in freezers build-up ice and frost and require regular defrosting. Conventional methods suspend the refrigeration process while a defrost mechanism heats the cooling elements with a heating element or hot gas. Once defrosted the refrigeration process may restart. Defrosting is typically controlled by a timer: for every six to twelve hours of refrigeration operation it turns on a defrost mechanism for fifteen to thirty minutes. While defrosting, the temperature in the freezer may rise. Because of a conventional defrost cycle's length and frequency, freezer burn or bacterial growth may occur. Conventional defrost heaters also use extra energy, typically have a power rating of 300 to 800 Watts. The energy expended in defrost heaters, drain heaters, timers, thermostats coupled with the wasted energy expended by the compressor coils makes current freezer technology inefficient.
Thus, there is a need in the art for efficient and environmentally friendly defrost methods for refrigeration and freezer systems.